A Goggle search: "John P. Gatewood" will pull up some 3 pages of hits, including this one:

Dr. Robert Scott Davis, Wallace State Community College, Hanceville, Alabama

"Civil War Guerilla Fighter John P. Gatewood." North Georgia Journal (Autumn 2000): 56-58.
http://www3.wallacestate.edu/bobdavis/docs/Biography_History.pdf